This invention concerns in general the communication of messages, i.e. data packages, between nodes or units interconnected by a transmission channel, for example the nodes of an electrical network on which the nodes transmit messages by means of carrier waves.
WO-A-2004/088871 describes a method for transmission of messages between an information collecting unit and a plurality of control units, combined with electrical equipment, for example lighting points in an urban area. The method provides for a particular method of transmitting the messages also over long distances in the presence of noise on the transmission channel, which in said case is represented by the electrical distribution network.
U.S. Pat. No. 4,692,761 describes a method for the transmission of information from reading units combined with electricity meters to a collecting unit. Each node combined with a meter sends the meter reading information to a collecting node by means of a complicated system for determination of the message path. In practice, the emitter node sends the message to a node below, chosen from a plurality of possible nodes below. This node below that receives the message forwards it again to the collecting unit by means of an analogous procedure, i.e. by choosing a node below it from a plurality of possible nodes below. In practice, the message path is determined in an adaptive manner step by step according to the conditions of the line, for example according to the noise present on the various portions of the electrical network along which the messages are propagated by means of carrier waves. This system is obviously very complex.